Armarctosaurus are some of the largest of the primitive retrosaurs, being as heavy as three modern elephants, and nearly as long as two. These animals have been found in only the northernmost parts of the northern hemisphere. Hailing from the Mid Jurassic period of Antarctica, Armarctosaurus fed on ferns and cycads, grinding them into paste with their serrated beak and enormous flat cheek teeth before swallowing for further digestion. The segmented armor along the animal’s back would have provided moderate defense against carnivorous primitive retrosaurs as well as early True Tyrants.

Although not a true amphibian, this primitive retrosaur adapted to a life on land and a life near the water. Hailing from the Triassic period of South America, this enormous retrosaur used the sail on its neck and shoulders to emote to other members of its species, and to display to anything that might think of trying to make a meal out of it, though that would not have been much of a problem for such a large predator. Dromaeobatrachus preyed upon lumbering herbivores like the South American cousins of the Armarctosaurus and was able to process small amounts of foliage from time to time, and would root up tubers as well as drive its large front fangs into the necks of contemporaries.

Seismoluros were some of the largest and most heavily armored Long Necked Goliaths to ever exist, as far as modern paleontologists are concerned. The beast was covered on its back with a segmented armor similar to today’s pangolin that started on the hump of the back, and continued to the tip of its whip-like tail, which terminated in a series of thagomizers and a mace-shaped club at the tip. It is thought the animal would not have been capable of terrestrial movement for very long due to its immense size, and it is very likely the leviathan spent most of its time in the Late Jurassic swamps of the Congo Basin. Its swamp dwelling nature is also backed up by the extended nostril tubules you see coming out of the snout, which acted like snorkels for the creature to breathe while submerged.

Much like the later Tyrannosaurus, Thanatorex were incredibly large and powerful predators. This form specialized in preying on the Long-Necked Goliaths and was one of the only Retrosaurs capable of following a Goliath into their swampy abodes, but even then, only for a while. For some reason, it seems the swamps and marshes were a great escape route for many Goliaths, as most are well-equipped with amphibious adaptations, so the only possible explanation posited by scientists is that these animals were trying to stay as far away from True Tyrants like the Thanatorex as best they could. The crest atop the snout of this beast was definitely used in battles between other tyrants and considering how pointy it looks it was probably a good weapon for subduing particularly troublesome Retrosaurs.

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Just like most Duck-Billed Goliaths, Gallititanus is were rather fond of the water and we know this because of the animal’s teeth and beak. Gallititanus had huge batteries of cheek teeth and a large spoon-shaped bill tipped with a slight pointed curve, which have allowed the beast to scoop up plant material from the swamps and grind it down to a fine paste. It is thought the animal could only chew on soft plant material because there is no reason to suspect it would have had any cheek muscles stronger than an average lizard considering the obviously reptilian nature of the remains that come from the Middle Cretaceous period of Bulgaria. This Duck-Billed Goliath would have been great fodder for larger True Tyrants like the European cousins of the Thanatorex, though using its crest as a snorkel would have been a great way to stay out of the way of the greater predatory Retrosaurs.

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There are not many Retrosaurs that were small in size, for it seems everything was bigger in the past. It is not known as to why this phenomenon occurs, but many think it was due to the increased levels of oxygen and food supply that allowed the Retrosaurs to become enormous in size, and none usually ventured to evolve smaller forms, the only exception being the Tiny Tyrants. These primitive Tyrants never evolved to bigger and better like their cousins, the True Tyrants, and were kept out of the sky by the Flying Tyrants. Deinopus got its name from the nearly 6-inch-long dagger-like claws cutting out the first toe. Like the raptorial Tiny Tyrants that have been thought to hunt in packs, Deinopus would have used these obviously killer claws to great effect probably going for the neck of much larger Retrosaurs. We have reconstructed the creature here with speculative frills on the shoulders and neck as a way to show that this animal was deadly and maybe even venomous; some researchers have the controversial opinion that the teeth of this animal show groove-like impressions that may correlate to venom glands in the mouth, but more research needs to be done and it is far from conclusive.

(Baed off of Coelophysoids, Dilophosaurids, and Dromaeosaurs of course)

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Clash! Crack! Bang! These are the noises that emanate from the batals between these thick-necked reptiles. As their name and their skulls suggest, Kentrocephalosaurus were some of the most well-defended bipedal herbivores that scientists know of! The almost punk-rock-like doem-shaped piece of solid bone atop this Helmeted Goliath’s skull was nearly 9 inches in thickness and would have protected the animal’s brain from collision forces, aided by the rigid muscles of the neck. The spines going down its neck have no obvious purpose, but it is thought they aided in keeping predators of its soft neck. Kentrocephalosaurus also used their big bulky acorn-like tails for counterbalances and could rattle them, as the armor was hollow and made of brittle keratin making a loud scary sound like the modern rattlesnakes to spook any unwanted attention.

(Based obviously of Pachycephalosaurs, but also rattlesnakes, while trying to push the anatomy of crazy head-banging lizards to the believable extreme)

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Eggs are full of protein, we all know this. Throughout the primordial swamps of ancient times, Retrosaurs had to reproduce and lay their eggs at some point, and their offspring were in danger at every turn. Before babies even get to breathe their first breath of air, they must first survive the Egg Thieves. Ovophagosaurus, from the Late Cretaceous of Australia was one prime example of these smaller Tyrants. Evolved to take advantage of the lackluster parenting skills of the dimwitted herbivorous Retrosaurs, Ovophagosaurus used its long arms and dexterous digits to snatch nutritious eggs from unsuspecting parents and cracked them open with the two sharp teeth on the roof of its mouth. Like some modern birds, Ovophagosaurus had an 8-inch-long claw on the inner toe. Long and flat, this was most definitely used to disembowel anything it desired to crush with its thick beak or as a defensive weapon to keep bigger and badder Retrosaurs away from it, only after its speed failed of course, for its long legs were obviously built for strong bursts of speed!

(Based on Oviraptorosaurs and Ornithomimosaurs, with just a dash of Cassowary)

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There were only a few ways to defend yourself as a Retrosaur in prehistoric times; Stand and fight or run away to live another day. Most of the large herbivores tended to go for the stand and fight strategy, quite an obvious observation what with their fancy suits of armor and defensive weapons, while smaller less-armored herbivores took to speed rather well. Machairacaudia was one of the most elaborate of the herbivorous Retrosaurs. As a Spike-Tailed Goliath, it should come as no surprise that this animal was covered from head-to-toe with spikes, plates, and defensive coverings. Specifically, this beast carried a bristling bush of sword-like spikes on the end of its tail topped off with a jewel-shaped club for an extra punch. Along its back sat enormous plates that probably helped regulate body temperature, for there was no way this creature was warm-blooded; much too reptilian. The plates become sharper and more pointed as they travel down the neck and back, towards the tail bush, resulting in an impressive defense which only the most dimwitted of predators would attempt to penetrate. This beast also carried with it a twin set of spikes that jutted forward from the shoulders to keep away predators from the front and to help it push through dense forests and strip the bark off of trees, since this herbivore was not picky and would have mowed down anything in sight no matter how hard to chew it was, which is backed up by the wide shape of the muzzle, and sharp teeth at the back of the mouth.

(Based on Stegosaurs and early Thyreophorans)

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Thunderous beats of massive bat’s wings would have been the last thing you’d have heard before being ripped to shreds between the talons of one of the largest and most ferocious Flying Tyrants yet discovered. Pelargotitanis got its name due to the enormous beak the animal had jutting out of its skull. Lined with teeth and sharpened like a blade, this Retrosaur was equipped with a maw more than ready and capable of disemboweling its quarry, aiding it in its task were the eagle-like talons on its hands and feet and the arrow-shaped club at the end of its sinuous tail. The reason for the arrow tip is not yet known, but many suspect it was purely for offense, using it is a blunt instrument to cause trauma to the heads of any unsuspecting herbivores. A ruler of land and air, Pelargotitanis only had to fear the open water, for when flying it was susceptible to being waterlogged if any denizens of the deep decided to take a bite.

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The most heavily armored of the Club-Tailed Goliaths so far discovered, Peloropelta was armored with teeth and every nook and cranny of this segmented behemoth was chock full of spikes, knobs, bone armor, and osteoderms to help keep away any predator in its environment. Originating from the latest Cretaceous period of Canada, this living tank very well may have had armor so thick and heavy, modern bullets would not have penetrated it! Above the animal’s shoulders were a pair of javelin-like spikes to stab anything that got too close without taking a bite, including other herbivores it didn’t want to be too close. The long thick tail that has an odd pinched anatomy near the middle, ends in a triple threat of symmetrical blades of bone ending in ridges that pinch closer together at their tip. This arrangement is like the sharpened blade of a battle axe and the condition is known by scientists as “Preternatural Sharpening,” and refers to the uncanny resemblance to modern weaponry but appearing naturally. The third aspect to the Peloropelta weaponry was the club that tipped the end of this battle-axe-like tail, so the entire tail could be swung in any direction and still hit its target. Scientists suggest the beast would have sharpened its tail on rocks and boulders it came upon while waddling about looking for its next meal of strong hard plants which it would slice and pulverize with its strong jaw muscles and sharp teeth. If there were ever a living fortress, one need not look further than Peloropelta.

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Hybocrassisaurus is easily one of the strangest Retrosaurs so far discovered. It wasn’t strange because of its wattles, spines, sails, and claws which it had plenty of, it was the strangest because it could easily walk on the balls of its feet with the heel firmly placed against the ground like a human foot, but never did so. Fossilized trackways have been found which suggest this animal dragged its back legs around walking on its knees like a toddler. For whatever reason it did this efficiently and did not need to move very fast very often. This animal was also almost certainly amphibious, for it had long fat claws and powerful arms that would have allowed it to dig burrows very easily aided by its scoop-shaped horn atop its snout and blunt stirrup on its chin. On its back was a sail-like structure held together with spines that would have been mobile beneath the skin which would allow it to be extended and retracted for use on land and for water propulsion. One of the few Retrosaurs to be a confirmed omnivore, it had the teeth and sharp beak to rend flesh and take down most small herbivores, but it also had the gut and molars for processing roots, tubers, and vegetation if need be.

(Based off of Anguirus and Baragon as well as Dimetrodon, Chameleons, Rhinoceros Iguanas, Green Iguanas, Godzilla)

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Transitional Tyrants were a group of tyrants that started to adapt to an aquatic lifestyle with some of them developing subterranean abilities, and some going more amphibious. Next to branch off were the Long-Necked Sea Tyrants. Unlike the Long-Necked Goliaths, these animals are carnivorous fish-eaters that trap their dangerous prey between the long needle-like teeth before swallowing them whole. Anguitherium is an example of this group that represents one of the largest and most terrifying so far discovered. This was not because you wouldn’t want to swim with it, which you wouldn’t, but because they were perfectly capable of coming out onto land and tearing into land animals, before delving back into the ocean depths. With their long necks and railroad-spike-like teeth, Anguitherium would find Flying Tyrants or early Birds flying over the water and strike with a viper-like intensity that would catch these flying creatures by surprise. Anguitherium has vestigial spurs on their front flippers that they use to help haul themselves onto land to chase after beach-dwelling transitional tyrants and goliaths but also more importantly to lay their eggs in large scrapes they dig in the beach dunes. After they lay their eggs, of which there are hundreds, they leave them to fend for themselves as most Retrosaurs do, and whoever survives, survives; Survival of the fittest!

(Based off Plesiosaurs, and outdated reconstructions of beach-walking Plesiosaurs)

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Adapted to ambush predation from the common Sea Tyrant ancestors, Long-Tailed Sea Tyrants are known for their obnoxiously long caudal vertebrae, with which they use to propel themselves in extreme bursts of speed to pursue their prey. Teratogyrinus is one of these apex marine predators adapted to prey upon a large array of prey. Specifically, they tended to go after larger prey, tearing off chunks until the animal died of blood loss. The claws on the front flippers of Teratogyrinus are vestigial with most of the usable length of the digit encased in the flipper. They would have used these claws to scrape mollusks off rocks, pinch fish out of crevasses, and even to scratch parasites off their bodies, but most experts suggest these predators would have hauled themselves out onto the beach to lay their eggs, but more research is needed to confirm this. It has become obvious with the fossil record, that Long-Tailed Sea Tyrants and Long-Necked Sea Tyrants were mortal enemies. Both could clamber onto land and both have been found in close proximity to one another on multiple occasions, so it would come as no surprise they attacked one another. It would seem the Long-Tailed Sea Tyrants had a stronger bite than the Long-Necked Sea Tyrants but were less maneuverable.

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There is a dizzyingly large array of Horned Goliaths, and this one is just as unique as the rest. Although not quite as near-and-dear to everyone’s hearts as Agathaumas, Carcinoceratops holds the record for spikes, wattles, and tusks. Its frill is merged with the flesh of its neck and back and muscle runs the lengths to help support the muscles needed to ram into opponents and to chew its food of bark, cycads, and other hard fruits. It is thought these animals fight one another for the rights to mate by clashing their horns and frills together, but this is not yet known and obviously these animals were none too bright, so a big show of dominance may have been all for not. Only more fossil remains will tell!

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The last of the three known types of Sea Tyrants were made up mostly of true titans! Short-Tailed Sea Tyrants were some of the largest creatures in the oceans of prehistoric times. The largest of them had heads nearly twice as long as human and railroad-spike sized teeth. Chelonosuchus was a heavily armored turtle-like beast with teeth shaped like the chompers of modern sperm whales it used to pulverize and puncture the fins of other marine animals. Most of the time they would have preyed upon Long-Tailed Sea Tyrants but literally anything else in the oceans would do, for Chelonosuchus were some of the largest ever found. Like all other Sea Tyrants, Chelonosuchus had a set of long, thin claws jutting out of the front flippers that could not be moved independently like true digits, and would have been used for many things, like intraspecific combat, food entrapment, and hauling themselves up onto beaches to lay their eggs.

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Pyroteratus is probably the strongest and most terrifying True Tyrant so far discovered. Titled the Apex Predator to kill all Apex Predators, this beast was armed to the teeth with recurved talons on its feet and hands, spines on its body for protection, a hard-spiny club on the end of its tail, forward and backward pointing horns on its head, and a pair of hollow teeth that very well may have been used to envenomate its prey. Why would such a large and intimidating creature need venom? Well, some scientists have suggested this antediluvian monster most definitely took down some of the largest Long-Necked Goliaths ever to walk the earth, using its large fangs to inject venom beneath the tough hide of the Goliaths and wait for it to die, or just start tearing into its prey as soon as it feels the fangs. It was named Pyroteratus due to its monstrous size and features, and due to its proximity to ancient volcanoes, obviously its natural habitat, making it all the more hellish of a beast.

(Based off of Acrocanthosaurus, Spinosaurus, and back when scientists thought Sinornithosaurus was venomous)

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